The kernel panics are caused by the switching between / to the AMD Radeon HD 6770M and the Intel HD Graphics 3000...

The first clue was that when logged out (timed) the graphics shown was the screensaver display dump and I had to move the cursor around to repaint the real screen info to see the user / password info to be able to log in again...

Then as the kernel panics occured I observed that most of them was in situations where there could be switching between the AMD Radeon HD 6770M and the Intel HD Graphics 3000...

The crash logs (many as there was many kernel panics) did not point to the graphics so that was of little help.

Re-installing to a new SSD, new RAM, disabling BluTooth etc., resetting NVRAM, running HWTESTS, verifying that the EFI and all other was up to date - the kernel panics was even worse... When booting after running HWTESTS I even got a kernel panic when booting..

I then disabled the Intel HD Graphics 3000 and have not had a single kernel panic / restart after that.

The original poster is having problems with it. And are you using it with the Logitech driver? Kernel extensions don't follow the expected rules for software. One running application should affect any other. Kernel extensions can and do interfere with each other. They are all part of the same processs.

I have investigated why my late 2011 17" MBP, 2.4GHz Intel Core i7, 4 or 16GB RAM, Mountain Lion 10.8.2, 750GB original HDD or 240GB SSD have been having the kernel panics.

I now know a lot more to the why, but not much more how to cure it properly...

I expect this problem are related to several MacBook Pro models as my findings indicate it to be a combination problem of SMC function and not optimal drivers and apps..

The short version are that the SMC are way to slow to increace the fan speed when the CPU get loaded, and the CPU temperature reaches over 90 degree Celsius (in seconds) before the fans have been able to become effective - they are just slowly starting to increase the speed when the MacBook Pro restarts due to overtemperature.

And that the SMC reduces fan speed or turns off the fans in several circumstances.

This last issue I have not investigated properly - I just disabled the Intel graphics (to lower CPU temperature and prevent temperature rise when switching to the Intel graphics), disabled the screensaver and automatic logout as these circumstances was causing problems.

I could not find any references to high temperature in the logs..

When the MacBook Pro reboots after a kernel panic the temperature are close to the dangerous area and the SMC have turned the fans off and it takes to long time to increase the speed again.

If the CPU usage during the boot are not to heavy the MacBook Pro may survive and run til the next time an application start using high CPU and the temperature again causes a kernel panic.

If the reboot process causes heavy CPU usage the temperature will reach the limit in seconds and a new kernel panic and reboot follows as the SMC starts the fans at the lowest speed and are not able to control the temperature in time.

Due to QTKitserver (QuickTime player) caused 117% CPU usage (observed even two processes giving a total of 234%) during boot after a kernel panic when playing the MacBook Pro went into a continious kernel panic / reboot loop. After that I removed the QuickTime player completely from the system...

I now also uses the scmFanControl app and have set the lowest fan speed to 2700 rpm - the smcFanControl app do allow SMC to control the fans normally, but I can change the fan speed to 4000 and 6200 rpm very fast.

Without QuickTime player and with the scmFanControl my MacBook Pro CPU now idles at 40 degree Celsius and the CPU load are below 1% (Total) when writing here, reading/writing emails, browsing websites without Flash etc.

Websites with Flash causes at least one CPU core to run at 50%..

When running applications that uses high CPU I must still increase the CPU fans manually to avoid kernel panics as SMC are ramping up the fan speed to slow.

The good news (for me) are that I now can use the MacBook Pro nearly normally again.

I hope a revised SMC algorithm will be presented soon, and that the kernel panic logs will updated with temperature information so all kernel panics caused by this can be easilly identified...

Maybe at a later point of time if not any fixes becomes available for download..

I have now stess tested the setup (with QuickTime player removed and the scmFanControl running).

Strangely enough the CPU usage are now overall reduced by a huge factor.

I started one Virtual Lion session, one Virtual Mountain Lion session, one Virtual Linux ubuntu session and one Virtual Windows XP session..

With all of them idling (including the Mountain Lion base system) the total CPU load are 5% and CPU temperature 50 degree Celsius. Running an autoruter (a huge PCB layout) in the Windows XP session increases the total CPU load to 15% and CPU temperature to 65 degrees Celsius..

Previously this would have caused problems after a short time due to high CPU usage and high temperature.

And everything now loads faster including Windows apps.. It feels like the MacBook Pro have become 3 - 4 times faster and uses 1/4 of the CPU resources to do it...

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